HK Logic 7 amp capacitor fried
#1
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HK Logic 7 amp capacitor fried
Hello,
My HK amp has a fried capacitor and I can't seem to find a match to replace. I have attached photos, hoping someone could give me some guidance. Thank you in advance.
My HK amp has a fried capacitor and I can't seem to find a match to replace. I have attached photos, hoping someone could give me some guidance. Thank you in advance.
#2
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MY'14 W212 M276 3.5NA @60kMi
mixed up
A: Power Amps B: caps
Take a good picture of the parts marking you are interested in replacing... or let's just say both A + B.This will help identify what parts were used.
#4
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MY'14 W212 M276 3.5NA @60kMi
Cajun style 🤪
I see... one of the power amp chip took out part of its circuit traces
overheated traces (not yet 100% cooked)
Do you want fix that? 70% this can be done successfully because these amps are all similar... you can compare reference measurements with nearby circuit .
See the 2 little "ceramic caps" are like a signature next to this chip: likely Spk. outputs (not a power feed) because there are repeated pattern.
Beside one or more TDA chips + caps.
For everyone... this is why you don't want to push this OEM amplifier enclosed in the trunk left side with restricted air circulation.
overheated traces (not yet 100% cooked)
Do you want fix that? 70% this can be done successfully because these amps are all similar... you can compare reference measurements with nearby circuit .
See the 2 little "ceramic caps" are like a signature next to this chip: likely Spk. outputs (not a power feed) because there are repeated pattern.
Beside one or more TDA chips + caps.
For everyone... this is why you don't want to push this OEM amplifier enclosed in the trunk left side with restricted air circulation.
Last edited by CaliBenzDriver; 07-25-2022 at 07:47 PM.
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MY'14 W212 M276 3.5NA @60kMi
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#8
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I have replaced this amp, don't want to spend too much since it would essentially be a spare. I figured I would give it a shot to repair myself if possible.
Last edited by anglil22; 07-25-2022 at 08:04 PM.
#9
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MY'14 W212 M276 3.5NA @60kMi
Amp markings
Read the markings off of your very own chip.
my HKL7 chip as sample (MY'14... Mfd'13)
It uses a different layout, so likely a different reference.
my HKL7 chip as sample (MY'14... Mfd'13)
It uses a different layout, so likely a different reference.
Last edited by CaliBenzDriver; 07-27-2022 at 07:10 PM.
#10
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MY'14 W212 M276 3.5NA @60kMi
fixing spare
What was wrong with bad channel: SPK shorted near zero from overheated coil insulation? This forced the amp to drive power into a shorted load maximum current + heat
Last edited by CaliBenzDriver; 07-25-2022 at 08:14 PM.
#11
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Easier said than done...LOL mine are not as clearly marked as yours.... I have attached a photo. Even with my readers on it is tough to make out the numbers. Yes, speaker shorted out. I replace it with identical since I upgraded my sound system and had to use the stock amp to integrate with an aftermarket.
Last edited by anglil22; 07-25-2022 at 08:30 PM. Reason: ADD TEXT
#12
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MY'14 W212 M276 3.5NA @60kMi
this is the designation marking
Do you read... "77B88ES" ?
You need to be sure!
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MY'14 W212 M276 3.5NA @60kMi
ghost
that's the part you have to buy.
I dont find matches, double check markings with a magnifying lens
I dont find matches, double check markings with a magnifying lens
#15
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Thanks, yes I tried a quick search and came up empty. I'll zero in on the markings and take it from there. I appreciate all your help! I'll chime in if I find it.
#16
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I found a working one on ebay for $240. It might be difficult to find the integrated circuit being sold anywhere. You will likely need to get one from a dead donor.
Maybe you'll get lucky and find someone selling a dead one on ebay.
Maybe you'll get lucky and find someone selling a dead one on ebay.
#17
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I saw that one. I'll keep poking around, as mentioned no rush. I was able to decipher the chip, picture attached. Unfortunately, haven't found one so far. Thanks again for your help!
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MY'14 W212 M276 3.5NA @60kMi
888... not lucky 🤪
that reference number looks like a short straw until a genius stops by with directions to the land of plenty...
Last edited by CaliBenzDriver; 07-26-2022 at 01:04 PM.
#19
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ebay.
#20
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that ST logo on the lower left of the last smallish picture is ST Microelectronics, https://www.st.com/content/st_com/en.html
that said, none of those numbers, with all sorts of variants, match any search, so its quite possible these are proprietary parts for Harman-Becker.
btw, surface mount soldering of chips like these is a lot trickier than regular soldering.
that said, none of those numbers, with all sorts of variants, match any search, so its quite possible these are proprietary parts for Harman-Becker.
btw, surface mount soldering of chips like these is a lot trickier than regular soldering.
#21
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I didn't know those things could be burnt out
#22
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MY'14 W212 M276 3.5NA @60kMi
specs say chips are foolproof
These chips being hard to toast, the circuit board Vias got overheated in the process
Last edited by CaliBenzDriver; 07-27-2022 at 03:03 AM.
#23
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13 s212 63 p30. 03 s55amg. 06 LX470
Smd repair
Smd repair is a nice skill to pick up. I recently picked up a nice hot air rework station and tools for my pinball machines. This can not be fixed with just a soldering iron. You need hot air, iron with a needle tip and magnifying lamp and a flux pen.
Chips are in short supply for everything, not just new items. Some for my pinballs are not scheduled to be made for 12 months.
Make sure to try mouser or digikey. Digikey will have a reference if it’s available anywhere.
the cost of the smd rework station and you time and the chip make this not an economic winner. I only repair expensive or out of production items and it made the station worthwhile.
good luck. That little cap is easy to find and the numbers are on them. but the chip will require a deep dive….alibaba if no others found. If they have it, that’s all there is.
Chips are in short supply for everything, not just new items. Some for my pinballs are not scheduled to be made for 12 months.
Make sure to try mouser or digikey. Digikey will have a reference if it’s available anywhere.
the cost of the smd rework station and you time and the chip make this not an economic winner. I only repair expensive or out of production items and it made the station worthwhile.
good luck. That little cap is easy to find and the numbers are on them. but the chip will require a deep dive….alibaba if no others found. If they have it, that’s all there is.
#24
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2014 Cummins, 2014 E250 Bluetec
Pointy iron and mag glass is what I used to repair smaller ones on a couple tablets. No hot air or flux pen. Granted I am not an electrician and if doing a bunch better ways but it is doable. I found some good instruction videos on doing it.
This is the soldering iron I picked up for doing the jobs It has performed pretty good for the random repairs I need it for.
Edit to add obviously good lighting, flux wick, tweezers, flux, basic soldering stuff required.
This is the soldering iron I picked up for doing the jobs It has performed pretty good for the random repairs I need it for.
Edit to add obviously good lighting, flux wick, tweezers, flux, basic soldering stuff required.
Last edited by Quint22; 07-27-2022 at 12:29 PM.
#25
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I have checked Moser and DigiKey and came up empty. Hopefully when chips become more readily available I will have some luck. Fortunately, not in a rush here.
Thanks to everyone for their help!
Thanks to everyone for their help!